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Malhotra, Mini

Publications and source records attributed to Malhotra, Mini.

At least 55 records · Page 3

Survey of existing and emerging power conversion technologies relevant to a self-powered furnace

Furnaces for residential space heating consume about 2.5% of all annual primary energy consumed in the US. Conventional furnaces utilize electricity from the electric grid to power blowers and other components. A self-powered furnace would utilize fuel energy to generate its own power, while rejecting the waste heat from the power cycle to provide additional useful building heating. Assuming the total energy use remains the same as for a conventional furnace, there are advantages in primary energy efficiency and operating cost. With no electrical connection to the grid, the self-powered furnace also improves resiliency to electric grid outages and reduces demand on the grid, which can be important during periods of peak heating. In addition, when unit size and venting type are maintained, a drop-in replacement with no incremental installation cost and increased potential for market adoption is achieved. In this work, the power generation requirements for such a drop-in-ready, self-powered furnace are analyzed, and available power generation technologies are surveyed.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Case Study for the ARRA-funded GSHP Demonstration at Furman University

With funding provided by the American Recovery and Reinvestment Act, 26 ground source heat pump (GSHP) projects were competitively selected in 2009 to demonstrate the benefits of GSHP systems and innovative technologies for cost reduction and/or performance improvement. One of the selected demonstration projects was proposed by Furman University for ten student housing buildings—the North Village located on the campus in Greeneville, South Carolina. All ten buildings are identical in floor plan and construction. Each building is conditioned by an identical GSHP system consisting of 25 water-to-air heat pump (WAHP) units, a closed-loop vertical ground heat exchanger (GHX) installed under an adjacent parking lot, and two redundant 7.5 hp variable-speed pumps to circulate water through the GHX and the WAHPs. The actual performance of the GSHP systems is analyzed with available measured data for 2014. The annual energy performance is compared with a baseline scenario in which the building is conditioned by air-source heat pumps (ASHPs) with the minimum allowed efficiencies specified in ASHRAE Standard 90.1-2013 (SEER 13 for cooling and 7.8 HSPF for heating) and supplemental electric heaters. The comparison is made in terms of energy savings, operating cost savings, cost-effectiveness, and environmental benefits. Finally, limitations in conducting this analysis are identified and recommendations for further improving the operational efficiency of the GSHP systems are made.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Case Study for the ARRA-funded Ground Source Heat Pump (GSHP) Demonstration at Wilders Grove Solid Waste Service Center in Raleigh, NC

High initial costs and lack of public awareness of ground-source heat pump (GSHP) technology are the two major barriers preventing rapid deployment of this energy-saving technology in the United States. Under the American Recovery and Reinvestment Act (ARRA), 26 GSHP projects have been competitively selected and carried out to demonstrate the benefits of GSHP systems and innovative technologies for cost reduction and/or performance improvement. This paper highlights the findings of a case study of one of the ARRA-funded GSHP demonstration projects, a distributed GSHP system for providing all the space conditioning, outdoor air ventilation, and 100% domestic hot water to the Wilders Grove Solid Waste Service Center of City of Raleigh, North Carolina. This case study is based on the analysis of measured performance data, construction costs, and simulations of the energy consumption of conventional central heating, ventilation, and air-conditioning (HVAC) systems providing the same level of space conditioning and outdoor air ventilation as the demonstrated GSHP system. The evaluated performance metrics include the energy efficiency of the heat pump equipment and the overall GSHP system, pumping performance, energy savings, carbon emission reductions, and cost-effectiveness of the GSHP system compared with conventional HVAC systems. This case study also identified opportunities for reducing uncertainties in the performance evaluation and improving the operational efficiency of the demonstrated GSHP system.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Health and Safety Audit Design Manual

The Health and Safety Audit is an electronic audit tool developed by the Oak Ridge National Laboratory to assist in the identification and selection of health and safety measures when a home is being weatherized (i.e., receiving home energy upgrades), especially as part of the US Department of Energy (DOE) Weatherization Assistance Program, or during home energy-efficiency retrofit or remodeling jobs. The audit is specifically applicable to existing single-family homes (including mobile homes), and is generally applicable to individual dwelling units in low-rise multifamily buildings. The health and safety issues covered in the audit are grouped in nine categories: mold and moisture, lead, radon, asbestos, formaldehyde and volatile organic compounds (VOCs), combustion, pest infestation, safety, and ventilation. Development of the audit was supported by the US Department of Housing and Urban Development Office of Healthy Homes and Lead Hazard Control and the DOE Weatherization Assistance Program.

47 OTHER INSTRUMENTATION↗

Evaluation of Variable Refrigerant Flow Systems Performance on Oak Ridge National Laboratory s Flexible Research Platform: Part 1 Cooling Season Analysis

This report provides second-year cooling season test results for the multi-year project titled “Evaluation of Variable Refrigeration Flow (VRF) System on Oak Ridge National Laboratory (ORNL)’s Flexible Research Platform (FRP).” The purpose of the second-year project was to (1) evaluate the full- and partload performance of VRF systems compared with an existing baseline heating, ventilation, and airconditioning (HVAC) system, which is a conventional rooftop unit (RTU) variable-air-volume (VAV) system with electric resistance heating and (2) use hourly building energy simulation to evaluate the energy savings potential of using VRF systems in major US cities. The second-year project performance period was from July 2015 through June 2016.

47 OTHER INSTRUMENTATION↗

Evaluation of Variable Refrigerant Flow Systems Performance on Oak Ridge National Laboratory s Flexible Research Platform: Part 2 Heating Season Analysis

The performance of two HVAC systems was evaluated using ORNL’s FRP, which is a two-story, 3,200 ft2 (297.3 m2) multi-zone unoccupied building that represents a typical low-rise, small office building common in the US existing building stock. The FRP is equipped with a conventional 12.5 ton (44 kW) RTU-VAV reheat system as the baseline system. For this study, a 12 ton (42 kW) VRF with a dedicated outdoor air system (DOAS) was installed to be compared with the baseline RTU system.

47 OTHER INSTRUMENTATION↗

Performance Analysis of a Ground Source Heat Pump System Using Mine Water as Heat Sink and Source

This paper summarizes a case study of an innovative ground source heat pump (GSHP) system that uses flooded mines as a heat source and heat sink. This GSHP system provides space conditioning to a 56,000 sq ft 2 (5,203 m 2 ) newly constructed research facility, in conjunction with supplementary existing steam heating and air-cooled chiller systems. Heat transfer performance and overall efficiency of the GSHP system were analysed using the available measured data from January through July 2014. The performance analysis identified some issues with using mine water for cooling and the integration of the GSHP system with the existing steam heating system. Recommendations were made to improve the control and operation of the GSHP system. These recommendations, in conjunction with the available measured data, were used to predict the annual energy use of the system. Finally, the energy and cost savings and CO 2 emission reduction potential of the GSHP system were estimated by comparing with a baseline scenario. This case study provides insights into the performance of and potential issues with the mine-water source heat pump system, which is relatively under-explored compared to other GSHP system designs and configurations.

42 ENGINEERING↗

Case studies for GSHP demonstration projects in the US

Under the American Recovery and Reinvestment Act , twenty-six ground source heat pump (GSHP) projects were competitively selected and carried out to demonstrate the benefits of GSHP systems and innovative technologies for cost reduction and/or performance improvement. This article gives an overview of the case studies for six of the systems. These case studies evaluated efficiencies, energy savings, and costs of the demonstrated systems. In addition, it was found that more energy savings could be achieved if controls of GSHP system are improved.

15 GEOTHERMAL ENERGY↗

Case Study for the ARRA-funded GSHP Demonstration at University at Albany

High initial costs and lack of public awareness of ground-source heat pump (GSHP) technology are the two major barriers preventing rapid deployment of this energy-saving technology in the United States. Under the American Recovery and Reinvestment Act (ARRA), 26 GSHP projects have been competitively selected and carried out to demonstrate the benefits of GSHP systems and innovative technologies for cost reduction and/or performance improvement. This report highlights the findings of a case study of one of the ARRA-funded GSHP demonstration projects—a distributed GSHP system at a new 500-bed apartment-style student residence hall at the University at Albany. This case study is based on the analysis of detailed design documents, measured performance data, published catalog data of heat pump equipment, and actual construction costs. Simulations with a calibrated computer model are performed for both the demonstrated GSHP system and a baseline heating, ventilation, and air-conditioning (HVAC) system to determine the energy savings and other related benefits achieved by the GSHP system. The evaluated performance metrics include the energy efficiency of the heat pump equipment and the overall GSHP system, as well as the pumping performance, energy savings, carbon emission reductions, and cost-effectiveness of the demonstrated GSHP system compared with the baseline HVAC system. This case study also identifies opportunities for improving the operational efficiency of the demonstrated GSHP system.

15 GEOTHERMAL ENERGY↗

The Weatherization Assistant User's Manual (Version 8.9)

The Weatherization Assistant is a Windows-based energy audit software tool that was developed by Oak Ridge National Laboratory (ORNL) to help states and their local weatherization agencies implement the U.S. Department of Energy (DOE) Weatherization Assistance Program. The Weatherization Assistant is an umbrella program for two individual energy audits or measure selection programs: the National Energy Audit Tool (NEAT) for site-built single-family homes and the Manufactured Home Energy Audit (MHEA) for mobile homes. The Weatherization Assistant User's Manual documents the operation of the user interface for Version 8.9 of the software. This includes how to install and setup the software, navigate through the program, and initiate an energy audit. All of the user interface forms associated with the software and the data fields on these forms are described in detail. The manual is intended to be a training manual for new users of the Weatherization Assistant and as a reference manual for experienced users.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Case Study of The ARRA-Funded GSHP Demonstration at the Natural Sources Building, Montana Tech

Under the American Recovery and Reinvestment Act (ARRA), 26 ground source heat pump (GSHP) projects were competitively selected in 2009 to demonstrate the benefits of GSHP systems and innovative technologies for cost reduction and/or performance improvement. One of the selected demonstration projects was proposed by Montana Tech of the University of Montana for a 56,000 sq ft, newly constructed, on-campus research facility – the Natural Resources Building (NRB) located in Butte, Montana. This demonstrated GSHP system consists of a 50 ton water-to-water heat pump and a closed-loop ground heat exchanger with two redundant 7.5 hp constant-speed pumps to use water in the nearby flooded mines as a heat source or heat sink. It works in conjunction with the originally installed steam HX and an air-cooled chiller to provide space heating and cooling. It is coupled with the existing hot water and chilled water piping in the building and operates in the heating or cooling mode based on the outdoor air temperature. The ground loop pumps operate in conjunction with the existing pumps in the building hot and chilled water loops for the operation of the heat pump unit. The goal of this demonstration project is to validate the technical and economic feasibility of the demonstrated commercial-scale GSHP system in the region, and illustrate the feasibility of using mine waters as the heat sink and source for GSHP systems. Should the demonstration prove satisfactory and feasible, it will encourage similar GSHP applications using mine water, thus help save energy and reduce carbon emissions. The actual performance of the system is analyzed with available measured data for January through July 2014. The annual energy performance is predicted and compared with a baseline scenario, with the heating and cooling provided by the originally designed systems. The comparison is made in terms of energy savings, operating cost savings, cost-effectiveness, and environmental benefits. Finally, limitations in conducting the analysis are identified and recommendations for improvement in the control and operation of such systems are made.

15 GEOTHERMAL ENERGY↗

Case Study of a Heating Only Central GSHP System Using a Shallow Aquifer for a Warehouse

High initial cost and lack of public awareness of ground source heat pump (GSHP) technology are the two major barriers preventing rapid deployment of this energy saving technology in the United States. Under the American Recovery and Reinvestment Act (ARRA), 26 GSHP projects have been competitively selected and carried out to demonstrate the benefits of GSHP systems and innovative technologies for cost reduction and/or performance improvement. This paper highlights findings of a case study of one of the ARRA-funded GSHP demonstration projects, which is a heating only central GSHP system using shallow aquifer as heat source and installed at a warehouse and truck bay at Kalispell, MT. This case study is based on the analysis of measured performance data, utility bills, and calculations of energy consumptions of conventional central heating systems for providing the same heat outputs as the central GSHP system did. The evaluated performance metrics include energy efficiency of the heat pump equipment and the overall GSHP system, pumping performance, energy savings, carbon emission reductions, and cost-effectiveness of GSHP system compared with conventional heating systems. This case study also identified areas for reducing uncertainties in performance evaluation, improving operational efficiency, and reducing installed cost of similar GSHP systems in the future. Publication of ASHRAE at the annual conference in Seattle.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗